1. Field of the Invention
The present invention relates to a webbing take-up device provided with a tension reducer capable of reducing a biasing force that biases a webbing that restrains the body of an occupant in a webbing take-up direction in an applied state of the webbing.
2. Related Art
Japanese Patent Application Laid-Open (JP-A) No. 2003-19946 (Patent Document 1) discloses a webbing take-up device (referred to in Patent Document 1 as a “seat belt winder for an automobile”) in which a reduction balance spring (referred to in Patent Document 1 as a “sub power spring”) is provided in addition to a take-up spring (referred to in Patent Document 1 as a “main power spring”) that biases a spool (referred to in Patent Document 1 as a “seat belt winder shaft”) in a take-up direction.
In a webbing take-up device such as that described in Patent Document 1, during transition of the reduction balance spring from a wound up state to a released state, a ratchet wheel rotates in a take-up direction relative to a ring due to resilient energy of the reduction balance spring, attempting to cause a portion in the vicinity of an inner end of the reduction balance spring to buckle in the radial direction outside. A special component referred to as a support member is accordingly used in the configuration described in Patent Document 1 in order to prevent or suppress such buckling of the portion in the vicinity of the inner end of the reduction balance spring.